1. Field of the Invention
This invention relates generally to continuous rolling mills of the type which produce rods, bars and the like, and is concerned in particular with an improved apparatus for driving successive roll stands at selectively different speed ratios.
2. Description of the Prior Art
In modern day rolling mills operating with widely varying rolling schedules and at extremely high speeds exceeding 100 m/sec., there is a growing need to drive successive roll stands with selectively different drive ratios. This is particularly true in rod mills, where so-called "mini" blocks are employed to further reduce and/or size entire families of products by selectively rendering inoperative or "dummying" preceding stands along the rolling line. The gear boxes of existing drive trains have various drawbacks and are either unable to adapt to the wide ranging demands imposed by current rolling schedules, or they are excessively large and expensive.
An objective of the present invention is to provide an improved gear transmission system which is readily adaptable to driving successive roll stands at multiple selectively different drive speed ratios.
Companion objectives include the provision of a multiple ratio gear box which is both compact and low cost as compared to conventional designs.